package openai

import (
	"net/http"
	"testing"
	"time"
)

// TestNew_DefaultTimeout verifies that a Config with no HTTPClient and no Timeout
// produces a Provider whose http.Transport has ResponseHeaderTimeout set to the
// package defaultTimeout (60s, cloud-appropriate).
func TestNew_DefaultTimeout(t *testing.T) {
	p := New(Config{APIKey: "test-key"})
	got := responseHeaderTimeout(t, p)
	if got != defaultTimeout {
		t.Errorf("ResponseHeaderTimeout = %v, want %v (defaultTimeout)", got, defaultTimeout)
	}
}

// TestNew_ConfigTimeout verifies that an explicit Config.Timeout propagates
// through to http.Transport.ResponseHeaderTimeout.
func TestNew_ConfigTimeout(t *testing.T) {
	want := 42 * time.Second
	p := New(Config{APIKey: "test-key", Timeout: want})
	got := responseHeaderTimeout(t, p)
	if got != want {
		t.Errorf("ResponseHeaderTimeout = %v, want %v", got, want)
	}
}

// TestNew_HTTPClientOverridesTimeout verifies that providing a custom HTTPClient
// takes full control: Config.Timeout is ignored, and the consumer's http.Client
// is used as-is.
func TestNew_HTTPClientOverridesTimeout(t *testing.T) {
	consumerTimeout := 7 * time.Second
	consumerClient := &http.Client{
		Transport: &http.Transport{ResponseHeaderTimeout: consumerTimeout},
	}
	p := New(Config{
		APIKey:     "test-key",
		HTTPClient: consumerClient,
		Timeout:    999 * time.Second, // deliberately wrong; must be ignored
	})
	got := responseHeaderTimeout(t, p)
	if got != consumerTimeout {
		t.Errorf("ResponseHeaderTimeout = %v, want %v (consumer's value)", got, consumerTimeout)
	}
	if p.client.HTTPClient() != consumerClient {
		t.Errorf("Provider is not using the consumer's HTTPClient")
	}
}

func responseHeaderTimeout(t *testing.T, p *Provider) time.Duration {
	t.Helper()
	hc := p.client.HTTPClient()
	if hc == nil {
		t.Fatal("Provider has nil http.Client")
	}
	transport, ok := hc.Transport.(*http.Transport)
	if !ok {
		t.Fatalf("Provider http.Client.Transport is %T, want *http.Transport", hc.Transport)
	}
	return transport.ResponseHeaderTimeout
}